Lab 2 Summary

8/10/2019 Lab 2 Summary

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Lab 2

Station 1

Use a skull model or specimen to locate the following structures.

- external occipital protuberance

- mastoid process (what is located within this structure?)

o mastoid air cells

- zygomatic arch (trace along its length to meet the temporal bone) What are the two

processes that unite to form this arch?

o Zygomatic process of the temporal bone and temporal process of the zygomatic

bone

- greater wing of sphenoid bone

- parietal eminences

- frontal eminences

-

glabella

- temporomandibular joint

- angle of the mandible hyoid bone (on yourself! squeeze gently, inferiomedial to the angle of

the mandible)

- spinous process of C3 and C7 Can you palpate the spinous process of C1?

o NoC1 does not have a spinous process

- clavicle: The medial one third of this bone is the origin for a large neck muscle that performs

the actions of flexion (when both left and right sides contract at once) and rotation (when

one side only is contracted).

o Identify (and palpate) the neck muscle described above: sternocleidomastoid muscle

(2 parts with insertions in sternum and clavicle and origin in the mandible)

-

manubrium (inferior to sternal notch) This bone is one of the two origins of a major neck

muscle (which also forms the boundary for the anterior and posterior triangles of the neck).

o Which neck muscle originates on the anterior surface of the manubrium?

Sternocleidomastoid

o Identify two other neck muscles that connect the posterior surface of the

manubrium to the:

Hyoid bone: sternohyoid

Thyroid: sternothyroid


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Station 2

INFRATEMPORAL FOSSA

- Anterior wall:maxillary tuberosity and pterygopalatine fissure

- Posterior wall:styloid process of the temporal bone

- Lateral wall:medial surface of the ramus of the mandible

-

Medial wall:medial pterygoid muscle- Roof:greater wing of the sphenoid bone

- Floor:medial pterygoid muscle

- Artery:maxillary artery

- Nerve:mandibular branch of the trigeminal nerve

o Mandibular branch splits into 2 divisions: anterior and posterior

Anterior division serves muscles of mastication

Posterior division splits into lingual nerve (supplies tongue) and inferior

alveolar nerve (passes inferior alveolar canal to supply posterior surface of

teeth)

-

Muscleso Insertion of the temporalis muscle

o Medial pterygoid muscle

o Lateral pterygoid muscle

- Vein:pterygoid plexus of veins

Trigeminalnerve (CN3)

Opthalmic

division

Maxillary division

Mandibular

division

Anterior branch

Posterior branch

Lingual nerve

Inferior alveolar nerve

Muscles of mastication

Tongue

Posterior

surface of the

teeth


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Station 3

External surface

Head

Neck

Condylar process (head & neck)

BodyRamus

Angle

Coronoid process

Mandibular (sigmoid) notch

Pterygoid fovea

Lingula

Mandibular foramen

Temporal crest (internal oblique line)

Retromolar fossa

Coronoid notch

Mental foramenMental protuberance

Mental tubercle

Alveolar Process

External oblique line (ridge)

Groove for the facial artery

Internal surface

Mylohyoid ridge (what attaches here?) mylohyoid muscle to form the floor of the oral cavity

Submandibular fossa (what sits here?) submandibular salivary gland

Sublingual fossa (what sits here?) sublingual salivary gland

Genial tubercles (mental spines/mental ossicles) (attached?)Digastric fossa (what attaches here?) anterior belly of the digastric muscle

Angle - attachment of medial pterygoid

Inferior alveolar canalinferior alveolar nerve of the posterior division of the mandibular branch of

the trigeminal nerve

Internal oblique ridge


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Station 5

Muscles of mastication

*When muscles contract, the insertion moves towards the origin

Muscle Origin Insertion Function

Primary muscles

Temporalis Superficial head:temporal fascia of the

temporal bone

Deep head:Temporal

fossa (inferior temporal

line) of the temporal

bone

Medial side of coronoidprocess of the mandible

Vertical fibers:elevationHorizontal fibers:

retraction

Unilateral:lateral

movement

Medial pterygoid Superficial head:

maxillary tuberosity of

the maxilla and

pyramidal process of

the palatine boneDeep head: medial

surface of the lateral

pterygoid plate of the

sphenoid bone

Internal side of the

angle of the mandible

Elevation

Lateral pterygoid Upper head:

infratemporal surface of

the greater wing of the

sphenoid between

foramen ovale and the

infratemporal crest

Lower head:Lateralsurface of the lateral

pterygoid plate of the

sphenoid bone

Upper head:Front of

the articular disk of the

temporomandibular

joint

Lower head:Pterygoid

fovea of the mandible

Bilateral (work together):

protraction

Unilateral (work

individually):lateral

movements

Masseter 3 heads (superficial,

medial and deep):

zygomatic arch

3 heads (superficial,

medial and deep):

lateral side of the ramus

of the mandible

Elevation

Assists in protraction,

retraction and lateral

movements

Accessory muscles

Digastric Posterior belly begins at

mastoid process of the

temporal bone

Anterior belly inserts

into digastric fossa of

the mandible

With hyoid bone

stabilized: elevation of

mandibleWith mandible stabilized:

helps in swallowing by

elevating hyoid bone

Mylohyoid Mylohyoid line of the

mandible

Hyoid bone With hyoid bone

stabilized: elevation of

mandible

With mandible stabilized:

helps in swallowing by

elevating hyoid bone


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Trial Exam

1. Identify the bony structure and the structures passing through it

Mental foramen: mental nerve and mental artery

2. Identify the bony structure and 1 structure that attaches to it

Coronoid process of the mandible: Temporalis muscle insertion

3. Identify the bony structure and 2 structures attached to it

Angle of mandible: Stylomandibular ligament, medial pterygoid muscle

4. Identify the bony structure and 2 structures attached to it

Genial tubercles: genioglossus muscle, geniohyoid muscle

5. Identify the bony structure and what passes through it

Foramen rotundum: maxillary branch of the trigeminal nerve

6. Identify the bony structure and what passes through itForamen magnum: spinal cord

7. Identify the bony structure and its function

Maxillary sinus: helps to reduce the weight of the skull, humidifies and makes the air more turbulent

8. Identify the bony structure and what passes through it

Stylomastoid foramen: facial nerve and stylomastoid artery

9. Identify the bone and name the pinned structure

Sphenoid bone: foramen spinosum

10. Identify the bone and 3 bones that articulate with it

Zygomatic bone: frontal, maxillary and temporal bones

Documents

Lab 2 Summary